Furnace resistor mounting



.J. C. WOODSON FURNACE RESISTOR MOUNTING Feb; 15 1927.:

Filed Nov. 28, 1923 INVENTOR James G Woodson.

WITNESSES:

ATTORNEY Patented Feb. 15, 1927 U N I T ;1.

ENT OFFICE.

JAMES C. WOON, OB' EAST PTTSBUE, PENNSYLVANIA, ASSIGNOR TO WESTING-HOUSE ELECTBIC & HAUFACTUBNG COMPANY, A COBPORATION OF PENNSYL- VANIA.

IUBNACE BEBTOR HOUNTING.

Application filed November 28, '1923. serial No. 877,!560.

invention relates to electrically heaturnaces and particularly toresistor mountings for electrically heated resistance furnaces. I Theobject of my invention is to provide a relativel simple resistormounting for an electrica ly heated resistor furnace.

In practicin my invention, I provide a pluralty of re ractoryheat-insulating walls e'nclosing a furnace chamber. In one or more ofsuch rwalls I mount a. plurality of spaced sets of relatively thin, elonated, metal members, of substantially T-s spe,

projecting into the furnace chamber. The' metal members of T-shape arespaced laterally in each ;set and relativel thin refractory plates orbars, having later& grooves in their inner surface, are held b the'outer ends of aire of members of T-s ape. A reiatively eavy resistor'member preformed to comprise a plurality of straight and substantially'parallel-extending, end-connected convolutions is held by the groovedpletes whereby the convolutions extend substan- 95 tiall arallel .to thefurnace wall and close ly jacent thereto;

'A substantially similar design is disclosed and claimed in condinapplication Serial No. 584,(320 of' A. I ei Electric & ManufacturingCompany. As set 'forth in that application, refractory members ofT-shape are supported by the "refractory walls of the furnace structureand, in order to dbtain suflicient strength,

the lateral area of the members of T sha e are made relatigely large andof such thic ness asto be substantially equal to the thickness of therefractory bricks or blocks emlo ed in buildin up the heat-insulating%nis g filed August* 30 28, 1922, and assigned to the Westinghouse-shape are of such thicknem that omprising the device embodying myinven- Fig. 2 is a. View, in perspectve, of a regctory grooved baremployed with the device embodying my invention,

Fig. 3 is a view, in perspective, of a devce embodying my invention,

Fig 4 is a view, in perspective, of a modified form of device embodyingmy invention and Fg. 5 is a View, in perspective, of a refracto baremployed with the modified form o metal supportingmember illustrated inFig., 4.

An electric furnace, designated generally by the numeral 11, comprisesan outer casing 12, of a suitable heat-insulating refractory materialusually employed in the art. An inner lining 13 is composed of aplurality of bricks or blocks of a suitable high-temperature resistingmaterial, a number of co-operating walls being provided, suitably spacedapart to form or enclose a furneoe chamber 14: of any suitable ordesired -cony tour and dimensione.

The furnace structure is illustrated schematically only' as the' deviceembodying my invention may be employed with any similar type of furnacecomprsing refractory walls occupyng a plurality of bricks or blocks inthe inner lining. y A plurality of spaced sets of relatively thin andelon atd metal members 15, of substantially -shape, are rovided in oneor more of the walls of the urnace structure 11. The members 15 areillustrated more particularly in Fig. 3 of the drawing, and comprise arelatively narrow, thin, and elongated main portion 16 and an integralflen portion 1 p thic ess of the main portion 16 is such ,that it me? beplaced between two successive layers o 'bric s or blocks comprising theinner linin 13, the binding material usually provid being omittedwherethe member 15 of T-shape is located.

The members 15 in the respective sets are,

spaced apart a suitable distance, and rela tvely narrowbars 18, of asuitable refractory electric-insulating material, extend between spacedpairs of members 15.` Each ofthe members 18 is provided, in one face.

at one end thereof The tween the `members 18 suppo thereof, with apluralty of spaced and laterally-extending grooves 19 and that face ofthe member 18 which is provided with the grooves 19 is normally locatedclosely adjacent to a surface of the wall supporting the members 15. v

A resistor member 21 of relatively heavy metal, preformed to comprise apluralit of straight and substantiallyparallel-exten ing convolutions,has parts of the individual convolutions located in the respectivegrooves 19 to extend therethrough and berted by the spaced sets ofmembers 15, substantially as illustrated in Fig. 1 of the drawing.

The end portions *of the respective re-` sistor members 21 are bent atsubstantially right angles to the plane of the convolutions and mayextend through suitable insulating bushings 22 provided in therespective walls of the Jfurnace structure.

In mounting the individual resistor members 21 in their proper operativepositions in the furnace structure, they are moved in a directionsubstantially at right angles to the plane of the convolutions and ofthe adjacent furnace wall so that the end portions will extend throughthe bushing 22 and the individual convolutions will be held temporarilyby the operator in substantially their proper operative positions. The.bars 18 may then be placed in their proper operative positions with apart of each convolution located in a groove 19, the bars 18 beingtemporarily located out of contact with the co-o rating supportingmembers 15 and move into their proper operative positions longtudinally`of !the convolutions.

As the resstor member 21 e'xpands and contracts duringthe normaloperation of the furn'ace, it is necessary `to provide means to reventmovement of the members 18 away rom the sup orting members 15, and Iprovide' relative y small key members 23 that are located on the'respective sides of the members 18 and extend through suitable openings24 in the members 15, closely adjacent to the flange portion 17.

In Fig., 4, I have illustrated a modified form of metal member 25 thatis rovided with a single opening adjacent t e 'oute'r end through whichextends a loc pin 26 that is easily and quickly remove therefrom. v

A refractory bar 27, having plurality of laterally-extending grooves 19in one sur-- -ace thereof, is provided with longitudinally extedinggro'oves 28 in that face o posite to the grooved face at each end of thebar. The longitudinal extent of the grooves 28 ia suflicient to rmit ofinserting and remov ing the hol ing iocated in thegrooves 28 of the twomem bers2'? operetiveiy euge any ose of members pin 26 which has its andWhen the modification of the metal sup porting member, illustrated inFig. 4-, is em plo ed, the method of assembly is slightly diirent fromthat described when member 15 is employed in that, after the resistormember 21 has been placed temporarily closely adjacent to one of thewalls, the respectve bars 27 may be placed in their proper o erativepositions by being moved toward t e surface of the wall it beingunderstood that the ins 26 have n removed 'from their normaFoperativepositions in the members 25.' After the bars 27 have been placed intheir proper operative positions closely adjacent to the co-operating'furnace wall and supported by, and extending between, the members 15,the holding or locking pins 26 may be dropped into their properoperative positions, thereby preventing any lateral movement of the bars27 away from the su porting members 15.

As urnaces of the type referred to in this a'p lication are intended too rate at relative y high temperatures, I emp oy metal members 15 or 25that are made of a metal that does not `otidize at such relatively hightemperatures and I may em loy nichrome or some similar material for t ispur As the distance between pairs o members 15 in the ree tive setsthereof cannot be made very ar e, on account of the strength of the memrs 18 and 27, the weight that each member 15 must support is' relativelsmall and, as the overhang thereof or t e distance which it rojects intothe furnace chamber may be mase relatively small the thickness of themain ortion 16 may made relatively very sma thereby permitting, as washereinbefore stated, the

nsertion of this member in place of the binding material provided tohold the adjacent layers of bricks or blocks together.

The device embodying my invention thus permits of coverin 'a muchgreater portion of the furnace wa s with a resistor member than would bethe case' if the sup rting members of T-shape were made of re ativelythich* refraetory material, as has heretofore been the case., As therooved refractory bars may be made relatvely narrow, substantially allof the resistor member 21 is left bare and in direct heat-radiatigrelation within the iurnace -chamber t ereby preventin any. pocketing ofthe' eat and possible ama e to the resistor.

erious m ifications and changes may be made without departing from thespirit and acope ot the' invention, and I desire., therefore, that onlysuch limitationa shall be steizal T-shape, and of substantialiy nonmeansoperatively associated with each memox a and projecting therefrom, anotched refracsaid bars laterally t` ereof.

tory bar, of electric-insulating material ex- In testimony whereof, Ihave hereunto 5 tending between each pair of metal memsubscribe& my namethis 20th day of Novembers, s. resistor member su porte& by said ber;1923.

`notehed refl-&story bars an being substantially self supportingtherebetweem, and JAMES C. WOODSON.,

e material, supported by said wall ber of 1'-shape for fireventingmovement of 10

